1. Grid References: 4-Figure vs 6-Figure
Remember the golden rule: "Along the corridor (Eastings) first, then up the stairs (Northings)."
- Eastings: Vertical grid lines that increase from Left to Right.
- Northings: Horizontal grid lines that increase from Bottom to Top.
- 6-Figure Grid Reference: Divide the grid square mentally into 10 equal tenths to locate points precisely (e.g., 345678).
2. Understanding Contour Lines
Contour lines connect points of equal height above sea level. Closely spaced contours indicate steep slopes; widely spaced contours indicate gentle slopes or flat land.
3. Measuring Distance and Calculating Bearings
Measuring Straight-Line Distance:
1. Measure distance between two points on the map with a ruler (e.g., 6.4 cm).
2. Use the map scale (e.g., 1:50,000 where 1 cm = 0.5 km).
3. Calculate real distance: 6.4 cm × 0.5 km/cm = 3.2 km.
1. Measure distance between two points on the map with a ruler (e.g., 6.4 cm).
2. Use the map scale (e.g., 1:50,000 where 1 cm = 0.5 km).
3. Calculate real distance: 6.4 cm × 0.5 km/cm = 3.2 km.